First electronic device for receiving power from second electronic device, method therefor, and second electronic device for transmitting power to first electronic device

Abstract

A first electronic device includes a first interface, a dummy load connected to the first interface, a first battery connected to the first interface and the dummy load, and a controller connected to the dummy load, where the controller is configured to receive power from a second electronic device through the first interface, identify a state of charge (SOC) of the second electronic device based on a packet received from the second electronic device through the first interface, and based on identifying that the SOC of the second electronic device is larger than a predetermined value and that the first battery is fully charged, conduct a direct current (DC) having a predetermined magnitude to the dummy load.

What is claimed is: 
     
         1 . A first electronic device, comprising:
 a first interface;   a dummy load connected to the first interface;   a first battery connected to the first interface and the dummy load; and   a controller connected to the dummy load,   wherein the controller is configured to:
 receive power from a second electronic device through the first interface; 
 identify a state of charge (SOC) of the second electronic device based on a packet received from the second electronic device through the first interface; and 
 based on identifying that the SOC of the second electronic device is larger than a predetermined value and that the first battery is fully charged, conduct a direct current (DC) having a predetermined magnitude to the dummy load. 
   
     
     
         2 . The first electronic device of  claim 1 , wherein the controller is configured to conduct the DC to the dummy load until a second battery of the second electronic device is fully charged. 
     
     
         3 . The first electronic device of  claim 2 , wherein the controller is further configured to, based on the second battery being fully charged or power reception from the second electronic device being stopped, stop conducting the DC to the dummy load. 
     
     
         4 . The first electronic device of  claim 1 , wherein the controller is further configured to:
 based on the first battery being fully charged, periodically conduct an alternating current (AC) having a predetermined magnitude to the dummy load; and   based on identifying that the SOC of the second electronic device is larger than the predetermined value and that the first battery is fully charged, conduct the DC to the dummy load and stop conducting the AC to the dummy load.   
     
     
         5 . The first electronic device of  claim 1 , wherein the controller is further configured to obtain the packet by receiving a signal magnitude-modulated with respect to a reference voltage or a reference current from the second electronic device through the first interface. 
     
     
         6 . The first electronic device of  claim 1 , wherein the controller is configured to conduct the DC to the dummy load based on a command received from the second electronic device. 
     
     
         7 . The first electronic device of  claim 6 , wherein the controller is further configured to obtain the command through the packet. 
     
     
         8 . The first electronic device of  claim 1 , wherein the first electronic device further comprises an optical element, and
 wherein the controller is configured to output light through the optical element based on identifying that the SOC of the second electronic device is larger than the predetermined value and that the first battery is fully charged.   
     
     
         9 . The first electronic device of  claim 1 , wherein the second electronic device is configured to wirelessly receive power from an outside. 
     
     
         10 . The first electronic device of  claim 1 , wherein the first electronic device comprises a wireless earphone, and
 wherein the second electronic device comprises a cradle on which the wireless earphone is mounted.   
     
     
         11 . A method of operating a first electronic device, the first electronic device comprising a first interface, a dummy load, and a first battery, the method comprising:
 receiving power from a second electronic device through the first interface of the first electronic device;   identifying a state of charge (SOC) of the second electronic device based on a packet received from the second electronic device through the first interface; and   based on identifying that the SOC of the second electronic device is larger than a predetermined value and that the first battery is fully charged, conducting a direct current (DC) having a predetermined magnitude to the dummy load.   
     
     
         12 . The method of  claim 11 , further comprising conducting the DC to the dummy load until a second battery of the second electronic device is fully charged. 
     
     
         13 . The method of  claim 12 , further comprising, based on the second battery being fully charged or power reception from the second electronic device being stopped, stopping conducting the DC to the dummy load. 
     
     
         14 . The method of  claim 11 , wherein conducting the DC to the dummy load comprises:
 based on the first battery being fully charged, periodically conducting an alternating current (AC) having a predetermined magnitude to the dummy load; and   based on identifying that the SOC of the second electronic device is larger than the predetermined value and that the first battery is fully charged, conducting the DC to the dummy load and stopping conducting the AC to the dummy load.   
     
     
         15 . The method of  claim 11 , wherein identifying the SOC of the second electronic device comprises obtaining the packet by receiving a signal magnitude-modulated with respect to a reference voltage or a reference current from the second electronic device through the first interface. 
     
     
         16 . The method of  claim 11 , wherein conducting the DC to the dummy load comprises conducting the DC to the dummy load based on a command received from the second electronic device. 
     
     
         17 . The method of  claim 11 , further comprising:
 outputting light through an optical element included in the electronic device based on identifying that the SOC of the second electronic device is larger than the predetermined value and that the first battery is fully charged.   
     
     
         18 . A second electronic device, comprising:
 a coil;   a second interface;   a rectifier circuit including a plurality of switches connected to the coil;   a regulator connected to the rectifier circuit;   a second battery connected to the regulator; and   a controller connected to the second battery, wherein the controller is configured to:
 while wirelessly receiving power from an external electronic device through the coil, transmit power to a first electronic device through the second interface, 
 transmit information on a state of charge (SOC) of the second battery to the first electronic device through the second interface, 
 when a size of current output from the regulator is greater than a designated current value, transmit a first command to the first electronic device so that the first electronic device conducts a direct current (DC) having a designated size to a dummy load included in the first electronic device, and 
 control the rectifier circuit so that the plurality of switches operate as a full bridge circuit until the second battery is fully charged when the SOC of the second battery is greater than a designated value. 
   
     
     
         19 . The second electronic device of  claim 18 , wherein the controller is configured to:
 transmit a second command to the first electronic device so that, when the second battery is fully charged, the first electronic device stops conducting the DC to the dummy load included in the first electronic device.   
     
     
         20 . The second electronic device of  claim 18 , wherein the controller is configured to:
 control the rectifier circuit so that, while a constant voltage is applied to the second battery, the plurality of switches operate as the full bridge circuit.